So, stepping back: rather than take a core vertically through relatively undisturbed ice, which is what Vostok or EPICA did, these folks have deliberately selected an area where the ice is flowing, bringing old ice near to the surface. And as it happens they drilled horizontally. So, you kinda get potluck for whatever you pull out. And as you can see from the figure (from the 1 Myr 2015 paper) it is much less fun to interpret (if it isn't obvious: what you get is the box with the rounded edges, and the dots inside): their Argon dating only gives them age to within ~100 kyr; and they can't pull out a continuous record, they just get a range.

1 Myr is only just outside the previous 800 kyr. 2.7 Myr is older; still, you'll notice that the Science article, while gushing, doesn't actually say much. Neither does their conference abstract: The old ice can be binned into three age groups: 1 Ma, 1.5 Ma, and 2+ Ma, disturbed by layers of ≤800 ka ice. This age-depth relationship indicates large-scale disturbance in the ice stratigraphy, reinforcing the concept of climate snapshots instead of time-series. Three climate proxies (Xe/Kr, δDice, and pCH4) fall within the range of variations in the recent 100-kyr glacial cycles, but with reduced variability. Hopefully, there will be more later.

Refs

* Now I "remember": it was CR who first pointed this out. Which has just made it's way to wiki.

More like this

A quiet day today (just as well after dinner and drinks last night with reprobate Jeff Ridley and somewhat more respectable John Turner). A bit of ice core stuff in the morning - using d-c-13 to understand glacial methane sources; trying to understand the 41kyr/100kyr switch in ice age cycles.
Pic…

10Be evidence for the Matuyama-Brunhes geomagnetic reversal in the EPICA Dome C ice core slipped by me when it was published last year (Nature 444, 82-84 (2 November 2006)). If they are correct, then its nice for the ice core folk because it provides an absolute tie-point into the marine records.…

Guest posting by (or rather, ripped from) Eric Wolff.
It is indeed a very fundamental question about whether the CO2 leads or lags the temperature. If there was somewhere in the ice core record where CO2 increases and temperature does not, then our understanding of the greenhouse effect must be…

Its evident that some people are still confused by the T/CO2 relationship, so I'll have another go in fairly simple terms.
Let me start with the "official" position, if you like. There are two cases: the current one, where we're pumping out CO2; and the ice age one, where CO2 varies naturally.…

Is the title mispelled?

[I take my spelling of "ancient" from Hobbes, because it sounds better :-) -W]

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It seems that the cat is out of the bag: scienceblogs is shutting down. Well, nothing lasts forever; or as Bowie - who also didn't last forever - put it: breaking up is hard, but keeping dark is hateful. I regret the close, partly as a disruption to my quiet routine but also as the end of someone'…

As the increasingly sparse readership of this blog will have noticed, I'm writeing less and less about science - science is hard, and increasingly GW science isn't terribly interesting, whatever James may say - and becoming increasing interested in the fringes of politics and philosophy, in which…

When I argued for treating GW as economics not morality, I didn't trouble myself to say "and I think it is easier to agree on economics than on morality", because it hadn't occurred to me that people might disagree. But of course, this is the internet, so people do disagree. CIP says so, for…

I seem to have run out of variations on Architecture and morality and Weasels ripped my flesh so I thought I'd drop the obscurity for once and use a simple post title which actually described the subject, rather than through several levels of indirection1.
The recent trigger to this was mt's The…

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“Devote yourself, but do not lose who you are!” -Marvel vs. Capcom
With Thanksgiving behind us, it's officially the holiday season here in the USA (and in many other places across the world), and so it's time to kick that off with a great holiday song by Calexico,
Gift X-change,
and to check out the fusion of two great holiday traditions: video games and seasonal sweaters!
Image credit:…

I'm sitting in a hotel in Utah at the PQE 2013 conference. As I write this, the temperature is a rather brisk 19F. (For everyone else in the world, -7.2C) That's not cold at all to some of you, but some of you didn't grow up in south Louisiana.
Once a year they let us grad students out of the basement!
Either way, on the Kelvin scale the weather here is still a balmy 267 degrees above absolute…

"What's in a name? That which we call a rose
By any other name would smell as sweet." -William Shakespeare
Up in the night sky, just a few degrees away from Orion, one of the most identifiable constellations in the winter sky, lies a cluster of newly formed stars.
Image credit: Stellarium. As always, click on all images for the highest-res version available.
5,000 light years away, this cluster…